I am trying to interpret the schematic for this IR sensor. I can figure it out, but I can't figure out that the 'uC' element is, and I don't think its micro-coulomb... Please help me determine this, or point me in the right direction.

The sensor does not have 3 outputs. The sensor receives the power/electricity through 2 pins. Page 4, lower right corner:
1 is Output of the sensor, this is the pin you hook up to the input of the uC.
2 is Ground.
3 is VCC, 2.1 to 5.5 volts.

Since you got this sensor info from arduino website, I would dig there and see how it was used with Arduino product.